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Doc's Gilbert Erector DEW Line Radar

Hi folks, Doc here. The next model in my "Radar Series", the DEW (Distant Early Warning) Line Radar, is an interesting one. Like the Satellite Tracker and Long Range Radar models it features compound movement. However, in this case the movement consists of a rotating curved radar panel and a smaller oscillating radar dish or cone. This can be seen in the accompanying video.

The main structure consists of a square raised platform constructed from MN base plates and DP 12" angle girders. The legs of the platform are BE 6" angle girders braced by B 5" flat girders. Atop the platform is a dome whose ribs are built from E 5" curved girders; these ribs are joined at the top of the dome to a ring composed of D 2½" curved girders. A BT pierced disk is anchored to the center of the ring with 2 H 11-hole strips, while a second BT disk is screwed to the center of the main platform. The main radar panel, constructed from E 5" curved girders, CH angles and N large double angles, rotates on an axle which passes through the two BT disks.


A small platform made from an MY base plate extends from one side of the main platform. It is supported from below by B 5" straight girders and P79 car trucks bolted to an MD base plate. A small radar cone made from a BN turret plate and a U boiler top is bolted to a P79 car truck and BT pierced disk. The BT disk is fixed to the upper end of an axle which goes through the center holes of the MY and MD base plates. A second BT disk, a CJ 36-tooth gear and a couple of short hole strips form a cam unit which connects to an A49 motor via an MZ bearing block and P48 mitre gears. When the motor is powered and the gearing engaged, the cam unit causes the radar cone to oscillate back and forth.


The same motor shaft which drives the mitre gears has a flexible coupling connected to its other end. This coupling in turn is connected to the shaft in the center of the main platform to which the main radar panel in attached. When the motor is under power this causes the radar panel to rotate within the dome.